Feed conduit for froth flotation machine



July 19, 1955 P. 1.. WIGTON FEED CQNDUIT FOR FROTH FLOTATION MACHINE Filed May 25, 1955 FIG.-- 4

INVENTOR. Paul L. Wigron ATTORNEY United States Patent 0 FEED CONDUIT FOR FROTH FLOTATION MACHHIE Paul L. Wigton, Denver, Colo.

Application May 25, 1953, Serial No. 357,161

4 Claims. (Cl. 209169) the feed to a single cleaner cell is the collected froth from a series of such rougher cells mixed with sufficient carrier liquid to form a free flowing pulp.

This pulp passes into a conduit or tube from a low point in a launder, and due to the presence of collector reagent from the previous flotation, the pulp is of very frothy consistency and frequently overloads the conduit resulting in a back pressure condition Which raises the froth level in the launder sometimes to the point of overflow, and also induces erratic feed to the cell.

Similarly when original feed to a cell passes first into a feed compartment and then into a feed conduit which delivers it onto the impeller, operating conditions develop which cause a back pressure that builds a false level in the feed compartment, and at times even the feed compartment will overflow.

It is an object of the present invention to provide a simple, durable and efficient feeding device for froth flotation cells which is arranged to offset backflow tendencies in the device.

Another object of the invention is to provide a simple durable and efficient feeding device having a lower passage for pulp and an upper passage for counter current removal of entrained gases of the pulp.

Still another object of the invention is to provide a recirculation control in froth flotation machines insuring The present invention is based on the discovery that by proper separation of the liquid and gaseous contents of a pulp being fed to a flotation cell it is possible to get a more uniform feed and also to prevent overflow of launders or feed compartments. Another part of the discovery resides in recognition that entrained gas of a flotation pulp may be collected in a separate passage and caused to flow in a reverse direction to the pulp flow and thereby reduce back pressure tendencies in the machine.

The practice of the present invention will be best understood by references to the accompanying drawings. In the drawings in' the several views of which like parts have been designated similarly,

Fig. 1 is a fragmentary perspective view of a flotation cell embodying features of the present invention;

Fig. 2 is a side elevation of a feed conduit of the type shown in Fig. 1, partially broken to show the arrangement of interior parts;

Fig. 3 is an end elevation of the intake section of the conduit shown in Fig. 2, looking in the direction of the arrows 33, Fig. 2; and

Fig. 4 is a side elevation of the return feed conduit shown in Fig. 1, partially broken away to shown the arrangement of interior parts.

As shown in Fig. 1, a cell C, preferably four sided, has a froth overflow (not shown) at the top of one of its sides, such as the front side wall 5. A rotary impeller 6 is carried at the lower end of a shaft 7 and agitates and mixes pulp, reagent and gas fed to the cell. Gas may be fed in any suitable manner, such as through the passage 8 in the hollow shaft. Pulp and reagent, preferably premixed or conditioned, enter the cell C from a feed compartment (not shown) through a feed conduit 9.

The machine illustrated in Fig. 1 is a Morse-Weinig Jetair Flotation Machine and the feed conduit 9 is of the type shown in Wigton Patent No. 2,502,497. This conduit comprises two sections 9a and 9b suitably flanged as shown at 10a and 10b respectively and bolted together. The hollow interior of the conduit is divided by a partition 12 into a lower major passage 13, and a narrow upper passage 14. The partition 12 extends substantially throughout the lengthwise extent of the conduit and has its forward edge 15 adjacent to shaft 7.

When the cell is used as a cleaner cell, a return feed conduit 18 is mounted on wall 5 for connection with the discharge outlet of a rougher-froth collection launder (not shown). This conduit has a partition 19 dividing its interior into a lower passage 20 and an upper passage 21 extending lengthwise of the conduit. Preferably section 9b of conduit 9 has a normally-sealed opening 22 into which the conduit 18 may be fitted.

When a cell, such as cell C, is provided with a feed conduit 9 and a return feed conduit 18, conditioned feed will be delivered from a feed compartment into conduit 9 from which it discharges onto impeller 6 and is mixed with gas and circulating pulp before discharge across the periphery into the pulp body in the cell.

At the same time rougher froth concentrate collected in a suitable launder flows into return feed conduit 18 and through opening 22 onto impeller 6. In the aforesaid actions, the pulp flow is through passage 13 of conduit 9 and passage 20 of conduit 18, while any back pressure condition developing at the impeller or in the conduits, or tending to develop, is relieved by gas entrainment in the passages 14 and 21 and its flow in counter current relation to a point of escape to atmosphere through the feed compartment or the launder.

The location of the partitions 12 and 19 and the size of the passages shown in the drawings may be varied to suit the requirements of a given machine design or of a particular treatment. All such variations may be availed of within the scope of the present invention as defined in the hereunto appended claims. It should be noted that either feed conduit may be used alone, or in combination as shown.

What is claimed is:

1. In a froth flotation cell, a rotary impeller in the lower portion of the cell, and a feed conduit extending from an exterior wall of the cell to a point of discharge over the impeller, said conduit having its interior divided by a lengthwise-extending partition into an upper gasconducting passage and a lower pulp-conducting passage.

2. In a froth flotation cell, a rotary impeller in the lower portion of the cell, and a feed conduit extending from an exterior wall of the cell to a point of discharge over the impeller, said conduit having its interior divided by a horizontally-disposed partition into an upper gasconducting passage and a lower pulp-conducting passage.

3. In a froth flotation cell, a rotary impeller in the lower portion of the cell, and tubular feed conduit extending from an exterior wall of the cell to a point adjacent the impeller, said conduit having its interior divided lengthwise by a horizontally disposed partition into a relatively small upper gas release passage and a relatively large lower pulp conducting passage.

4. In a froth flotation cell, a rotary impeller in the upper portion of the cell, and an oval feed conduit extending from an exterior wall of the cell to a point over the impeller, said conduit being formed of two members having a flange on at least one end thereof and being bolted together, said conduit having its interior divided by a lengthwise extending partition into a relatively small upper gas release passage and a lower relatively large pulp conducting passage.

References Cited in the file of this patent UNITED STATES PATENTS 

